The present invention relates to a metal encapsulated or enclosed multi-phase high voltage switching system filled with compressed gas for single or multiple double bus-bar systems.
More particularly, the present invention relates to a switching system of the above-type which is provided with protective walls, equipped with passages, for gas-tightly partitioning the system into the following protected chambers: (1) a switch chamber including a high voltage switch in the form of a power or load break switch, and cable terminals electrically connected with the switch and penetrating the enclosure or encapsulation; and (2) a bus bar chamber for each bus bar system accommodating the respective bus bars and a respective disconnect or three-way switch for each phase connected with the bus bars. Moreover, the protective walls of the switching system are also provided with bushing-type current pins which extend through the passages to electrically connect the two protected chambers, and the poles of the power or load switch are arranged next to one another in a straight line or slightly offset with respect to the front of the switching system.
A system having the above features is known under the name "Steel Sheet Protected, SF6 Insulated Switching System Series ZV2" and is described in Publication No. 1376/14 of Color-Emag ElecktizitAts-Aktiengesellschaft of Ratingen, Federal Republic of Germany, and is composed of a plurality of block-shaped modules which are closed in themselves and are thus separated from one another. The modules each include an operational chamber, e.g. a bus bar chamber. To be able to assemble a complete switching system, the modules of several operational chambers must be combined through the intermediary of gas-tight passages.
In view of the use of block-shaped housings, the known switching system makes it possible to encapsulate or enclose its simple framework in planar sheet metal. To be able to reliably manage the pressures developing during operation or in case of malfunction, without having to make the metal sheets of the encapsulation too thick, these metal sheets are reinforced by additional measures, e.g. ribs welded to their interior or exterior faces.
In the known system, the block-shaped housing modules make it possible to arrange all three bus bars of a system in a plane parallel to the closest covering. Since the bus bar disconnect switches also provided in this module are oriented phase by phase according to the poles of the power switch, the connecting lines between the bus bars and the disconnect switch poles are intertwined and cross over one another. Thus the bus bar chambers have a relatively great depth and, for that reason, they are disposed above or below the switch chamber.